Hip flexors dominate — legs swing instead of pelvis curling
No spinal flexion occurs; hip flexors do all the work.
Overactive muscles
Hip flexorsRectus femoris
Corrective work
Foam RollHip flexors↗StretchHalf-kneeling hip flexor stretch↗Core · Core
Reverse Crunch
Coaching cues
- Supine; hands at sides or gripping bench; legs at 90°
- Curl the pelvis toward the chest — posterior pelvic tilt
- Hips lift slightly off the floor at the top
- Lower under control — don't let the hips crash down
Common faults 2
Momentum swings legs up
Kinetic energy rather than muscle contraction lifts the hips.
Overactive muscles
Hip flexorsErector spinae
Corrective work
Foam RollHip flexors↗StretchHalf-kneeling hip flexor stretch↗